Promote ArrayDeque and MutableList.removeFirst/LastOrNull to stable

libraries/stdlib/src/kotlin/collections/ArrayDeque.kt

@@ -13,8 +13,8 @@ package kotlin.collections
  * The collection provide methods for convenient access to the both ends.
  * It also implements [MutableList] interface and supports efficient get/set operations by index.
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 public class ArrayDeque<E> : AbstractMutableList<E> {
     private var head: Int = 0
     private var elementData: Array<Any?>

libraries/stdlib/src/kotlin/collections/MutableCollections.kt

@@ -236,29 +236,29 @@ public inline fun <T> MutableList<T>.remove(index: Int): T = removeAt(index)
 /**
  * Removes the first element from this mutable list and returns that removed element, or throws [NoSuchElementException] if this list is empty.
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 public fun <T> MutableList<T>.removeFirst(): T = if (isEmpty()) throw NoSuchElementException("List is empty.") else removeAt(0)
 
 /**
  * Removes the first element from this mutable list and returns that removed element, or returns `null` if this list is empty.
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 public fun <T> MutableList<T>.removeFirstOrNull(): T? = if (isEmpty()) null else removeAt(0)
 
 /**
  * Removes the last element from this mutable list and returns that removed element, or throws [NoSuchElementException] if this list is empty.
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 public fun <T> MutableList<T>.removeLast(): T = if (isEmpty()) throw NoSuchElementException("List is empty.") else removeAt(lastIndex)
 
 /**
  * Removes the last element from this mutable list and returns that removed element, or returns `null` if this list is empty.
  */
-@SinceKotlin("1.3")
-@ExperimentalStdlibApi
+@SinceKotlin("1.4")
+@WasExperimental(ExperimentalStdlibApi::class)
 public fun <T> MutableList<T>.removeLastOrNull(): T? = if (isEmpty()) null else removeAt(lastIndex)
 
 /**